Quatre, you can call Costco's customer service number at 800-955-2292 and request the summer coupon book: that's what I did since I didn't receive one either, and it took about two weeks for it to arrive in the mail.
I asked one of the well known Samsung calibraters that posts here frequently, and he couldn't comment on the 6756 since he hasn't evaluated it. I would hope that the new model will be at least as good as the 6767 which was quite spectacular. My guess is that the coupon will bring the price down to 2299 in August.
I have to wonder about the 62" height dimension. I have a 61" Sony std def XBR, and according to Samsung's stated height w/stand, the Sammy is taller than my massive Sony. When I'm standing next to the Sammy in Costco, I think that there's no way that this thing is taller than my old Sony. (the sony has extra height because of the heavy furniture-like top and the thick base with casters). This is important to me because I need the Samsung to be shorter in order to convince my wife to let me get it.

pgibbons: you're welcome!

On a side note: Costco online has the Samsung 6156 for 1999 with a stand.